I went from the stock rubi 32s on 17s to Super Swamper 34s on 16s and haven't noticed that big of a difference in on-road handling. I think you'll be OK with 16s unless you go w/a really big tire (lots of sidewall) - say 35s or 37s. If you're thinking 33s - I wouldn't give it a second thought and go with the 16s.
07 Jeep Green Rubi Unlimited, auto
Mods: Tuffy Cubby Storage Cover, Rugged Ridge grab handles, Shrockworks Sliders, Rock Hard Engine / Gas Tank Skids, Rhino-lined tub, Kilby Evap Can Relocation Kit, 16x8 Centerline Wilderness Series - Falcon Rims, 285/75/16 Interco SSRs, OME 2" HD Lift, PSC Diff Covers, Superwinch EPi 9.0, BulldogFab Rear Bumper, RedrockFab Front Bumper and skid